Performance of a lead rubber damper under cyclic shear loading and its applicability to a full-scale structure

In this paper, we investigate the performance of a new lead rubber damper (LRD) and its applicability to a full-scale structure. This device is more advanced than existing lead-rubber based isolation devices. In contrast to the existing devices, multiple lead cores are installed in the LRD in order to enhance the performance of the laminated rubber and lead. It is able to perform effectively under the application of shear force. An experiment was performed to investigate its dependency on the level of shear strain and frequency. The applicability of this new device to a full-scale structure is also examined by performing a vibration test on a five floor modal-test tower

Pre-transplant crossmatch-negative donor-specific anti-HLA antibody predicts acute antibody-mediated rejection but not long-term outcomes in kidney transplantation: an analysis of the Korean Organ Transplantation Registry

BackgroundPre-transplant donor-specific anti-human leukocyte antigen antibody (HLA-DSA) is a recognized risk factor for acute antibody-mediated rejection (ABMR) and allograft failure. However, the clinical relevance of pre-transplant crossmatch (XM)-negative HLA-DSA remains unclear.MethodsWe investigated the effect of XM-negative HLA-DSA on post-transplant clinical outcomes using data from the Korean Organ Transplantation Registry (KOTRY). This study included 2019 living donor kidney transplant recipients from 40 transplant centers in South Korea: 237 with HLA-DSA and 1782 without HLA-DSA.ResultsABMR developed more frequently in patients with HLA-DSA than in those without (5.5% vs. 1.5%, p<0.0001). Multivariable analysis identified HLA-DSA as a significant risk factor for ABMR (odds ratio = 3.912, 95% confidence interval = 1.831–8.360; p<0.0001). Furthermore, the presence of multiple HLA-DSAs, carrying both class I and II HLA-DSAs, or having strong HLA-DSA were associated with an increased incidence of ABMR. However, HLA-DSA did not affect long-term clinical outcomes, such as allograft function and allograft survival, patient survival, and infection-free survival.ConclusionPre-transplant XM-negative HLA-DSA increased the risk of ABMR but did not affect long-term allograft outcomes. HLA-incompatible kidney transplantation in the context of XM-negative HLA-DSA appears to be feasible with careful monitoring and ensuring appropriate management of any occurrence of ABMR. Furthermore, considering the characteristics of pre-transplant XM-negative HLA-DSA, the development of a more detailed and standardized desensitization protocol is warranted

Enhancing Signaling Flux via Light-Induced Assembly of the Mitogen-Activated Protein Kinase (MAPK) Pathway

Liquid-liquid phase separation of macromolecules occurs in many cellular contexts. The functions of the resulting droplets, however, have been less well understood. One hypothesized function of protein droplets specifically is to locally increase the concentration of enzymes and substrates, enhancing reaction rates and allowing for greater flux through cellular pathways. This hypothesized function makes protein phase separation an appealing avenue for synthetic biology because it allows one to design stimulus-responsive droplets to concentrate proteins of interest and tune flux. However, the limits of this hypothesized function remain unexplored, making it difficult to determine which pathways would benefit from synthetic cluster formation. To explore the hypothesis that clustering could enhance flux through a signaling pathway, we set out to create light-responsive droplets containing model kinase-substrate pairs drawn from MAP kinase signaling pathways. Using the p38 pathway as a model system, we find that light-induced clustering and light-induced heterodimerization achieve similar levels of flux enhancement. Furthermore, in agreement with the idea that local concentration affects signal enhancement, we find that if components of the p38 pathway are already co-localized through a linker, clustering has no effect. Similarly, the JNK pathway, which contains an endogenous scaffold protein, does not show flux enhancement when clustered. We use the results from this study to suggest that scaffold proteins co-localize proteins in order to mediate flux in kinase pathways, though further testing is needed. Ultimately, the findings in this work contribute to establishing a better understanding of the effects of liquid-liquid phase separation and the role of scaffold proteins in the context of cellular pathways

Enhancing Signaling Flux via Light-Induced Assembly of the Mitogen-Activated Protein Kinase (MAPK) Pathway

Liquid-liquid phase separation of macromolecules occurs in many cellular contexts. The functions of the resulting droplets, however, have been less well understood. One hypothesized function of protein droplets specifically is to locally increase the concentration of enzymes and substrates, enhancing reaction rates and allowing for greater flux through cellular pathways. This hypothesized function makes protein phase separation an appealing avenue for synthetic biology because it allows one to design stimulus-responsive droplets to concentrate proteins of interest and tune flux. However, the limits of this hypothesized function remain unexplored, making it difficult to determine which pathways would benefit from synthetic cluster formation. To explore the hypothesis that clustering could enhance flux through a signaling pathway, we set out to create light-responsive droplets containing model kinase-substrate pairs drawn from MAP kinase signaling pathways. Using the p38 pathway as a model system, we find that light-induced clustering and light-induced heterodimerization achieve similar levels of flux enhancement. Furthermore, in agreement with the idea that local concentration affects signal enhancement, we find that if components of the p38 pathway are already co-localized through a linker, clustering has no effect. Similarly, the JNK pathway, which contains an endogenous scaffold protein, does not show flux enhancement when clustered. We use the results from this study to suggest that scaffold proteins co-localize proteins in order to mediate flux in kinase pathways, though further testing is needed. Ultimately, the findings in this work contribute to establishing a better understanding of the effects of liquid-liquid phase separation and the role of scaffold proteins in the context of cellular pathways

Enhancing Signaling Flux via Light-Induced Assembly of the Mitogen-Activated Protein Kinase (MAPK) Pathway

Liquid-liquid phase separation of macromolecules occurs in many cellular contexts. The functions of the resulting droplets, however, have been less well understood. One hypothesized function of protein droplets specifically is to locally increase the concentration of enzymes and substrates, enhancing reaction rates and allowing for greater flux through cellular pathways. This hypothesized function makes protein phase separation an appealing avenue for synthetic biology because it allows one to design stimulus-responsive droplets to concentrate proteins of interest and tune flux. However, the limits of this hypothesized function remain unexplored, making it difficult to determine which pathways would benefit from synthetic cluster formation. To explore the hypothesis that clustering could enhance flux through a signaling pathway, we set out to create light-responsive droplets containing model kinase-substrate pairs drawn from MAP kinase signaling pathways. Using the p38 pathway as a model system, we find that light-induced clustering and light-induced heterodimerization achieve similar levels of flux enhancement. Furthermore, in agreement with the idea that local concentration affects signal enhancement, we find that if components of the p38 pathway are already co-localized through a linker, clustering has no effect. Similarly, the JNK pathway, which contains an endogenous scaffold protein, does not show flux enhancement when clustered. We use the results from this study to suggest that scaffold proteins co-localize proteins in order to mediate flux in kinase pathways, though further testing is needed. Ultimately, the findings in this work contribute to establishing a better understanding of the effects of liquid-liquid phase separation and the role of scaffold proteins in the context of cellular pathways

Defluorinative C–C Bond-Forming Reaction of Trifluoromethyl Alkenes with <i>gem</i>-(Diborylalkyl)lithiums

We report the transition-metal-free defluorinative C-C bond-forming reaction of trifluoromethyl alkenes with gem-(diborylalkyl)lithiums. This synthetic strategy provides access to a variety of 4,4-difluoro homoallylic diboronate esters, which serve as versatile intermediates in the efficient preparation of valuable gem-difluoroalkene derivatives. Further synthetic modifications are conducted to demonstrate the synthetic utility of the obtained 4,4-difluoro homoallylic diboronate esters. © 2022 American Chemical Society. All rights reserved.11Nsciescopu

Characterization of the Propagation of Meteorological Drought Using the Copula Model

Drought is a phenomenon that is caused by several factors and can be divided into meteorological drought, agricultural drought, hydrological drought, and socioeconomic drought. In this study, the characteristics of propagating from meteorological drought to agricultural (or hydrological) drought in the Andong Dam basin and Hapcheon Dam basin located in the Nakdong River basin in Korea were investigated. Standardized precipitation index (SPI), standardized soil moisture index (SMI), and standardized runoff index (SRI) were used to characterize meteorological, agricultural, and hydrological droughts, respectively. SPI-m (1–12) on various timescales and SMI-1 (or SRI-1) were selected as drought propagation timeseries, such that a correlation analysis was performed to evaluate the correlation and propagation time between meteorological and agricultural (or hydrological) drought. Propagation probability was quantified using a copula-based model. The correlation between meteorological and agricultural (or hydrological) droughts was not significantly affected by seasons. A relatively strong correlation was found in summer. A relatively weak correlation was shown in autumn. In addition, it was found that there was a difference in correlation between the Andong Dam basin and the Hapcheon Dam basin. On the other hand, in both watersheds, the propagation time was as long as 2 to 4 months in spring and decreased to 1 month in summer

Characterization of the Propagation of Meteorological Drought Using the Copula Model

Drought is a phenomenon that is caused by several factors and can be divided into meteorological drought, agricultural drought, hydrological drought, and socioeconomic drought. In this study, the characteristics of propagating from meteorological drought to agricultural (or hydrological) drought in the Andong Dam basin and Hapcheon Dam basin located in the Nakdong River basin in Korea were investigated. Standardized precipitation index (SPI), standardized soil moisture index (SMI), and standardized runoff index (SRI) were used to characterize meteorological, agricultural, and hydrological droughts, respectively. SPI-m (1&ndash;12) on various timescales and SMI-1 (or SRI-1) were selected as drought propagation timeseries, such that a correlation analysis was performed to evaluate the correlation and propagation time between meteorological and agricultural (or hydrological) drought. Propagation probability was quantified using a copula-based model. The correlation between meteorological and agricultural (or hydrological) droughts was not significantly affected by seasons. A relatively strong correlation was found in summer. A relatively weak correlation was shown in autumn. In addition, it was found that there was a difference in correlation between the Andong Dam basin and the Hapcheon Dam basin. On the other hand, in both watersheds, the propagation time was as long as 2 to 4 months in spring and decreased to 1 month in summer

Changes in Adolescent Health Behavior and the Exacerbation of Economic Hardship During the COVID-19 Pandemic: A Cross-sectional Study From the Korea Youth Risk Behavior Survey

Objectives: This study investigated the association between exacerbated economic hardship during the coronavirus disease 2019 (COVID-19) pandemic and changes in the health behaviors of Korean adolescents. Methods: We analyzed data from the 2021 Korea Youth Risk Behavior Survey and included 44 908 students (22 823 boys and 22 085 girls) as study subjects. The dependent variables included changes in health behaviors (breakfast habits, physical activity, and alcohol use) that occurred during the COVID-19 pandemic. The aggravation of economic hardship by COVID-19 and the subjective economic status of the family were used as exposure variables. Multiple logistic regression analysis was utilized to calculate the prevalence odds ratios (PORs). Results: Severe exacerbation of a family’s economic hardship due to COVID-19 was negatively associated with the health behaviors of adolescents, including increased breakfast skipping (POR, 1.85; 95% confidence interval [CI], 1.55 to 2.21 for boys and POR, 1.56; 95% CI, 1.27 to 1.92 for girls) and decreased physical activity (POR, 1.37; 95% CI, 1.19 to 1.57 for boys and POR, 1.38; 95% CI, 1.19 to 1.60 for girls). These negative changes in health behaviors were further amplified when combined with a low subjective family economic status. Conclusions: The experience of worsening household hardship can lead to negative changes in health behavior among adolescents. It is crucial to implement measures that address the economic challenges that arise from stressful events such as COVID-19 and to strive to improve the lifestyles of adolescents under such circumstances